TY - JOUR
T1 - Hydrothermal synthesis of magnetite crystals
T2 - From sheet to pseudo-octahedron
AU - Hu, Ming
AU - Ji, Rui Ping
AU - Jiang, Ji Sen
PY - 2010/12
Y1 - 2010/12
N2 - In this paper, we developed a hydrothermal method to fabricate sheet-like and pseudo-octahedral magnetite crystals. X-ray diffraction (XRD) confirmed the products were pure spinel-structured magnetite. Scanning electron microscopy (SEM) was used to investigate the morphology of the obtained crystals. By carefully regulating the initial NaOH concentrations, the morphology of the products could be changed from sheet-like crystals to pseudo-octahedral crystals. Transmission electron microscopy (TEM) analysis indicated the sheet-like crystals were the oriented aggregation of nanoparticles. Pseudo-octahedral magnetite crystals were single crystalline, and were obtained by dissolution-recrystallization of the sheet-like crystals. Vibrating sample magnetometer (VSM)) suggested the magnetic properties of the products were strongly related to the morphology. The coercivity of the sheet-like magnetite crystals was 100 Oe, larger than 30 Oe of the pseudo-octahedral crystals, but the saturation magnetization of the sheet-like magnetite crystals was 40 emu/g, smaller than 85 emu/g of the pseudo-octahedral crystals.
AB - In this paper, we developed a hydrothermal method to fabricate sheet-like and pseudo-octahedral magnetite crystals. X-ray diffraction (XRD) confirmed the products were pure spinel-structured magnetite. Scanning electron microscopy (SEM) was used to investigate the morphology of the obtained crystals. By carefully regulating the initial NaOH concentrations, the morphology of the products could be changed from sheet-like crystals to pseudo-octahedral crystals. Transmission electron microscopy (TEM) analysis indicated the sheet-like crystals were the oriented aggregation of nanoparticles. Pseudo-octahedral magnetite crystals were single crystalline, and were obtained by dissolution-recrystallization of the sheet-like crystals. Vibrating sample magnetometer (VSM)) suggested the magnetic properties of the products were strongly related to the morphology. The coercivity of the sheet-like magnetite crystals was 100 Oe, larger than 30 Oe of the pseudo-octahedral crystals, but the saturation magnetization of the sheet-like magnetite crystals was 40 emu/g, smaller than 85 emu/g of the pseudo-octahedral crystals.
KW - A. Magnetic materials
KW - B. Chemical synthesis
KW - B. Crystal growth
KW - D. Magnetic properties
KW - D. Microstructure
UR - https://www.scopus.com/pages/publications/78649315611
U2 - 10.1016/j.materresbull.2010.09.023
DO - 10.1016/j.materresbull.2010.09.023
M3 - 文章
AN - SCOPUS:78649315611
SN - 0025-5408
VL - 45
SP - 1811
EP - 1815
JO - Materials Research Bulletin
JF - Materials Research Bulletin
IS - 12
ER -